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GENEVOIS OARS.

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no longer to resist the water :" this mechanism being absolutely free from the ten objections in his oar, he joined together the two qualities in the pattern, its swiftness and its non-resistance in the return by making oars with a joint at the feather, which expanded so as to be quite flat when opposed to the water in acting, to impel the boat forwards; and to fold almost together, and oppose no resistance to the water when they were withdrawing from it;-like a duck's foot, closing as it comes forward, and opening as it is drawn back *.

His "great principle," which was to consider "springs as a magazine or repository of all the powers which are lodged in them, and to make them restore with violence, or with weight and measure, any power bestowed on them," he applied as the intermediate means of moving his natural oar. To bend the springs, he describes a sort of

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We quote the following anecdote from his pamphlet, "It is true, an honourable gentleman, one of the mem. bers of the Navy Board, told me, when I appeared before them in August, 1764, that, about thirty years ago, a Scotchman proposed to make a ship sail with gunpowder; but having found by the experiments made for that purpose, that thirty barrels of guupowder had scarce forwarded the ship the space of ten miles, this invention had been rejected. To this I answered, that he acquainted me with a thing quite new to me; that his scheme was deservedly rejected, but that my work was of another kind. I have since been told, that it was by the retrogradation of one or more cannons on the poop, this man had conceived the hope of forwarding a ship. This put me in mind of the trial a celebrated gentleman made, many years ago, to set a boat going on the Rhine, by the effusion of the water from a tub on the stern, by a hole towards the prow; this was only as short. As for the Scotchman's work, one may easily see it has nothing in common with mine, but the thought of gunpowder." -Inquiries tending to the Improvements of Navigation, p. 20. London, 1760.

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AUXIRON'S EXPERIMENT.

cannon with a piston, in which he ignites gunpowder: but Genevois is here noticed as proposing to bend his springs, which move his oars, by Newcomen's engine. Before, however, he submitted his plan to the Commissioners, he had. their pledge that they would warrant to him the merit of the invention; " but I desire all equitable persons to believe, that I had some reason to act in this manner, drawn from considerations more honest and suitable to the character. I have the honour to be invested with, than the mean views of a contemptible vanity. I durst flatter myself," says the worthy pastor," that discoveries so useful to mankind in general, might be so to my family."

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But this scheme, which had been proposed by many, and attempted unsuccessfully by three experimenters, was now to have a fair trial. The Comte d'Auxiron*, who had already appeared before the public with advantage, succeeded, in 1774, in bringing a scheme for moving boats by a steamengine, before a number of individuals who associated for the purpose of enabling the Marquis to carry his plan into execution. The experiment was tried on the Seine, near Paris; but the engine, by which the wheels were propelled, not

*The COMTE D'AUXIRON was a native of Basançon, and a member of a family, whose father and brothers devoted to the sciences, adorned their favourite studies with some estimable performances. He was born in 1728, and entered the army at an early age, in which he held the rank of a captain of artillery; the duties of his profession interfering with his tastes, he solicited his dismission, and retired in 1765. the same year, he published a proposal for supplying Paris with water, and continued afterwards to publish occasionally treatises on philosophical subjects. In 1769 he printed a Theory of Rivers, and means for preventing the ravages of Floods, a work evincing much observation. He died at Paris in 1778.

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AUXIRON'S STEAM-BOAT.

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having the necessary force, the boat moved so slowly and irregularly, that the company, at whose expense the trial had been made, considered the result offered no inducement to persevere; and judging from what they had seen, navigation by steam, in their opinion, could not supersede, either on the score of speed or economy, the ordinary method of towing by horses.

Perier, the elder*, since well known in France as an able and accomplished mechanic, assisted at this experiment; and, notwithstanding the discouraging opinion, formed by many of his friends

JACQUES CONSTANTIN PERIER, a Member of the French Academy of Sciences, was a native of Landes, and the eldest of three brothers who were bred millwrights. His second brother AUGUSTUS CHARLES, was his colleague during his whole life. The third brother died when a very young man. The centrifugal pump, which they constructed as their first essay, was placed in the gallery of mechanical models, formed by the Duc d'Orleans, and for its merit is yet preserved in the Conservatoire des Arts et Metiers, at Paris. Jacques Constantin, that he might acquire more profoundly the elements of his art, made journeys to England, The year he returned from his first visit, he was employed by the government to erect engines on the Isle de Cignes to supply the place of the water-wheels, which had been stopped by a rigorous winter; when the urgency had passed, the millers left the machines to their fate. During the early part of the revolution, the Periers cast cannon and other warlike stores for the state. But the fall of the assignats, with which they had been paid, almost crushed them. And the government, as if to consummate their ruin, refused to listen to their claims for compensation. In these times, they employed their work. men in fabricating engines in general demand by manufac turers. The manufactory, which still flourishes, and ranks as the first in point of excellence and extent in France, has produced a great number of steam-engines, which have been erected in all parts of the continent, and are esteemed for their excellent workmanship. Jacques Constantin also established the foundery at Liege for casting cannon. He died at Paris, in 1818, in the 76th year of his age. He was the author of a small treatise on steam-engines.

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PERIER'S STEAM-BOAT.

from the Marquis's failure, he repeated the trial, with some improvements in the mechanism, in the following year. The steam-engine he used was an imperfect model which had been laying about his workshop, of a power about equal to that of one horse. This was placed in a boat, and attached to two wheels, one at each side, with a contrivance to give them a rotary motion. The performance of the model was as defective as that used by d'Auxiron, and the boat moved but slowly against the current of the Seine. This trial not being so favourable as Perier had anticipated, he did not proceed further with his experiments; as the project did not now appear to offer any temptations for him to go on with it, in preference to some others, to which he had devoted his time, and in which he had embarked his capital.

The Marquis Ducrest, who was present at Perier's exhibition, gives a good account of it; but his impression was decidedly in favour. of its being easily practicable to move boats by a steam-engine; he explains, in a very satisfactory manner, why that no inference ought to be drawn, as to the speed of vessels navigated in this manner from this experiment, because it was not fairly made. For, instead of a boat of this size being propelled by an engine, having a power only of one horse, it ought, according to his calculation, to have been furnished with one having the power of four or five horses to have driven the wherry against the stream of the Seine, with so small a velocity even as that of the towed boats, or from three and a half to four miles an hour*. Fortified by this opinion,

Essais sur les Machines Hydrauliques, p. 184. Paris, 1777.

PRONY'S STATEMENT.

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Perier did not altogether abandon the subject, and in succeeding years he made a few attempts in substituting other mechanism for that of the paddle-wheels, which he thought were defective substitutes for oars, and which in his view occasioned his failure. But he was too languid in the pursuit to accomplish so great a matter: his attempts do not appear to have excited much attention in France, and no traces appear of their having been noticed in England.

It was two years after his first experiment with his steam-boat, that Perier formed a company for supplying the city of Paris with water. In his own manufactory, which at that time ranked as the first in France, he made steam-engines; yet with an honourable acknowledgment of the superiority of those manufactured by their great inventor, he came to England, and succeeded in inducing Bolton and Watt to sell him an engine on their best construction, and with all their latest improvements. He remained at Birmingham during its fabrication, and procuring a license from the English government for its exportation, he carried it to Paris, and by the assistance of two skilful mechanics, who accompanied him from Soho, and the instructions he had received from Bolton and Watt, he erected it at Chaillot. This is the engine described by Prony, in his splendid book on the Steam-Engine, who is minute even to prolixity in describing its parts; but omitting to state to whose talents the beautiful mechanism was due, he encouraged the inference that Perier was its inventor, as well as its fabricator. Yet Prony, who ranked as one of the most liberal and the most accomplished scientific men of his time, happened to be that individual, under whose immediate direction Perier was despatched to England, who

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